Pharmaceutical compositions and method of inhibiting gastric acid secretion

ABSTRACT

Pharmaceutical compositions and methods of inhibiting gastric acid secretion by administering N-alkenyl and N-alkynyl thioamides.

United States Patent [191 Loev [ 51 July 29, 1975 [73] Assignee: SrnlthKIlne Cbt'porltlon,

Philadelphlm-Pm' 22] Filed: Apr. 12, 1974 2n A 1.No.=46o.ars

name us. :Appllcatlo n Dita" [63]- Contlnultlon-ln-part of Ser.=-No.-255.828, May 22.

1972, Pat. No. 3,825,547.

[52 us. CL; 424/263; 424/248; 424/250;v

[5 l] Int. Cl Afillt 27/00 Eidmlner-Frederlck E. Weddell Attorney; Agent, or Flrm- -Joan S. Kept; Rlchard D. Fogglo', William H. Edgerton 7 [5 7] ABSTRACT Pharmaceutical composition! and methods bf inhibitin; 'g'agtric acid secretion by administering N-alkenyl and N-alkynyl thioamides.

10 Claims, No Drawlnga l PHARMACEUTICAL COMPOSITIONS AND METHOD OF INIIIBITING GASTRIC ACI SECRETION This application is a continuation-in-part of application Ser. No. 255,828 filed May 22, 1972. new US. Pat. No. 3,825,547. i

This invention relates to new N-alkenyl and N- alkynyl thioamides having pharmacological activity. In particular, these compounds inhibit gastric acid secretion.

The compounds of this invention are represented by the following formula:

FORMULA l in which:

R, is 2-pyridyl, Z-pyrimidyl, 4-pyrimidyl, Z-pyrazinyl, 2-pyrrolyl, 2-quinolyi, 2thiazolyl or 4-thiazolyl;

R, is hydrogen, lower alkyl, lower alkenyl, lower alkoxy, allyloxy, cyclopropanemethoxy, phenyl, benzyl or z)n 4 si R is an allyl or propargyl group optionally substituted by methyl or ethyl groups, said R, having 3-6 carbon atoms;

R and R, are lower alkyl or taken together with the nitrogen atom to which they are attached form a piperidino, pyrrolidino, morpholino or N-lower 'alkylpiperazino ring and n is or i. a

This invention also includes pharmaceutically acceptable acid addition salts of the compounds of Formula l. I I

The pharmacologically active compounds of this invention have the basic structure of Formula I'. However. it is apparent to one skilled in the art that well known nuclear substituents such as lower alkyl, lower alkoxy or halogen may be incorporated on the phenyl and heterocyelic rings. These substituted compounds are used as are the parent compounds.

Preferred compounds of this invention are represented by Formula I in which R ishydrogen, lower alkyl or C,NR,R,,, R is allyl optionally substituted by methyl or ethyl. said R having 3-6 carbon atoms and R and R, are methyl or ethyl or taken together with the nitrogen atom to which they are attached form a piperidino. pyrrolidino or morpholino ring.

Advantageous compounds of this invention are represented by Formula I in whichR, is 2-pyridyl, R is hy-- drogen, lower alkyl or morpholinomethyl and R, is al- Most preferably, in the compounds of Formula I. R, is Z-pyridyl.

Particularly advantageous compounds of this invention are N-allyl-2-(2-pyridyl)thioacetamide and N- allyl-3-morpholino-2-(Z-pyrldyl)thiopropionamide.

The Compounds of this invention produce inhibition of gastric acid secretion. This activity is demonstrated by administration to pylorus ligated rates at doses of about 2.0 mg./kg. to about 50 mg./kg. orally. in this procedure. compounds which produce an increase in gastric pH or a decrease in the volume of gastric juice or both are considered active.

The compounds of this invention are prepared by the following procedures:

R, RI

CH- NH N-R, CH- -NHR R,

RI n

\ (i) has:

a, (2) R,-NCS a/ 5 According to procedure i. a substituted thloacetamlde is reacted with an alkcnylannlne or alkynylamine to give the N-aikenyl and N-alkynyl thioamides of this invention. The reaction may be run at 20 to l00C. but is preferably carried out at about 0 to 5C. The reaction may be run in aqueous or non-aqueous systems. Excess of the amine may be used as solvent. The use'of an aqueous system is preferred.

According to procedure II, a methyl (or substituted methyl) heterocycle is reacted with strong base such as phenyl or butyl lithium and then with an alkenyl or alkynyl isothiocyanate to give the N-alkenyl and N- alkynyl thioamides.

The compounds of Formula I in which R, is -CH- ,-NR R,, may be prepared by reacting the compounds of Formula I in which R, is hydrogen with formaldehyde and the appropriate amine.

The pharmaceutically acceptable acid addition salts of thecompounds of Formula I are formed with organic and inorganic acids by methods known to the art. For example. the base is reacted with an organic or inorganic acid in aqueous miscible solvent, such as acetone or ethanol, with isolation of the salt by concentration and cooling or in aqueous immiscible solvent, such as ethyl ether or chloroform, with the desired salt separated directly. Exemplary of the salts which are in- Preferably. the compounds are administered in conventional dosage forms prepared by combining an appropriate dose of the compound with standard pharmaeeutical carriers.

Pharmaceutical compositions having gastric acid secretion inhibitory activity, in dosage unit form, comprising a pharmaceutical carrier and a gastric acid secretion inhibiting amount of a compound of Formula I or pharmaceutically acceptable acid addition salt thereof are objects of this invention.

The pharmaceutical carrier may be for example a solid or a liquid. Exemplary of solid carriers are lactose. magnesium stearate. terra alba, sucrose. talc. stearic acid. gelatin. agar, pectin. acacia or cocoa butter. The amount of solid carrier will vary widely but preferably will be from about 25 mg. to about i gm. Exemplary of liquid carriers are syrup, peanut oil, olive oil, sesame oil, propylene glycol, polyethylene glycol (mol. wt. 200-400) and water. The carrier or diluent may include a time delay material well known to the art such 3. as. for example, glyceryl monostearate or glyceryl distearate alone or with a wax.

A wide variety of pharmaceutical forms can he employed. for example the preparation may take the form of tablets, capsules. powders, suppositories. troches. lozenges, syrups. emulsion. sterile injectahle liquids or liquid suspensions or solutions.

The pharmaceutical composition are prepared by conventional techniques involving procedures such as mixing. granulating and compressing or dissolving the ingredients as appropriate to the desired preparation.

The methods of inhibiting gastric acid secretion in accordance with this invention comprise administering internally to an animal an effective amount of acompound of Formula l or a pharmaceuticaily acceptable acid addition salt thereof. The active. ingredients will preferably be administered in dosage unit form as described above.

The compounds of'this invention will'be adminisy tered in a daiiy'dosage regimen of from about l mg. to about 2 g., preferably from about 25 mg. .to about i g. Advantageously. equal doses Wiiifb administered one to'four times per day. Dosage units will contain from about l0 mg. to about 500 mg., preferably from about 25 mg. to about 250 mg., of the active ingredient.

When administration is carried out as described,

above, gastric acidsecretlon is inhibited.

One skilled in the art will recognize'that in determining the amounts of the active ingredients in the claimed compositions and used in the claimed methods, the ac tivity of the chemical ingredient as well as the size of the host animal must be considered.

The terms lower alkyl" and lower alkoxy where used herein denote groups having, preferably, l-4 carbon atoms; lower aikenyl denotes groups having, preferably, 2-4 carbon atoms and "halogen" denotes chloro, bromo or fluoroa The following examples are not trative of the invention.

EXAMPLE I A solution of 9.3 g. (0.l mole) of 2-picoline in 50 ml. of anhydrous ether is added dropwise at l5C. to 50 ml. of a 2.lM solution of phenyl lithium in benzene/ether limiting butare .11....

under nitrogen. The resulting mixture is stirred for one hour. then added dropwise to a stirred solution of 9.9 g. (0.l mole) ofallyl isothiocyanate in 200 ml. of anhydrous ether at --50C. under nitrogen. The mixture is stirred for minutes after the addition is complete and thenpouredinto 150ml. of dilute hydrochloric acid/ice and stirred. The layers are separated "and-the aqueous phase is basified with 5 percent aqueous sodium carbonate solution acetate. The extracts are dried and concentrated and the residue is recrystallized from benzene/petroleum ether to give N-allyl-2-(2-pyridyl)thioacetamide. m.p. 6768C.

EXAMPLE 2 To 4.0 g. (0.026 mole) of 2-(2-pyridyl)thioacetamide in ml. of water at 0C. is added 2.9 g. (0.053 mole) of propargylamine with stirring and the resulting suspension is allowed to stand overnight at 5C. Ethanol (5 ml.) is added and the mixture is stirred for 5 hours, then extracted with dichloromethane. The extracts are dried and concentrated. The residue is chromatographed on a silica gel dry-column". using l:l() ethyl and then extracted with ethyl acetate/ether as the eluant. The product fraction is treated with charcoal. filtered. concentrated and the residueis recrystallized from bcnzene/ligroin to give N-propargyl-2-( 2-pyridyl )thioacetamide. m.p. 62-63.C.

EXAMPLE 3 A solution of 5.0 g. (0.026 mole) ofN-allyl-Z-(Z- pyridyllthioacetamide in 80 ml. of methanol is treated at C. with 3.4 g. (0.039 mole) of morpholine and Li? g. (0.039 mole) of formaldehyde and the mixture is stirred for 24 hours.

The solvent is evaporated at 25C. and the resulting oil is triturated with petroleum other until crystallization is complete. Recrystallization from ether gives N- allyl-3-morpholino-2-(Z-pyridyl)thiopropionamide. m.p. 84-86" C.

EXAMPLE 4 A solution of 9.95 g. (0.08l mole) of Z-(methoxymethyl)-'pyridine in 80 ml. of dry benzene is added dropwise to a'chilled solution of 40 ml. (0.084 mole) of phenyl lithium in 8 0 ml. of dry. benzene. The mixture is stirred 'at 0C. for 1 hour after the addition is complete.

Then 8.02 g. of allylisothiocyanate in 50 ml. of henzene is added dropwise and the mixture is allowed to come to room temperature gradually. The mixture is then diluted with 500 ml. of water and acidified with it) percent hydrochloric acid. The layers are separated .and the organic layer is washcd several times with water. The aqueouslayers are combined, neutralized with 10 percent aqueous sodium hydroxide solution and then brought to pH 9 with .5 percent aqueous sodium bicarbonate solution. then extracted with chloroform. The chloroform extracts'are washed once with brine and dried over magnesium sulfate. The solvent is removed arid the residueis chromatographed on a silica gel column. eluting 'with ethyl acetate. The fractions containing the product are combined and evaporated and the residue is recrystallized from ethyl acetate/hexane to give N-allyl-2-methoxy-2-(2-pyridyl)- thioacetamide, m.p.' 59.5-euc.

EXAMPLE 5 By the procedure of Example i. using in place of 2- picoline. the following compounds:

5 N-allyl-2-( Z-pyrazinyl )thioaeetumide N-allyl-2-( Z-pyrimidyl )thioacetamide N-allyl-2-(4-pyrimidyl )thioaeetamide N-allyl-2-( Z-pyrrolyl )thioncetamide N-allyl-2-( Z-quinolyl)thioaeetamide N-allyl-2-( Z-quinolyl )thiopropanamide N-allyl-2-( 2-thiazolyl )thioacetumide N-allyl-2-(2-thiazolyl)thiopropanamide N-allyl2-phcnyl-2-( Z-thiazolyl )thioaeetamide N-allyl-2-(4-thiazolyl)thioacetamide.

EXAMPLE (1 Using 2-l2-(dlmethylumlno)ethyllpyrldlnu In place of 2-picoline i the procedure of Example I. the product is N-allyl-3-dimethylamino-2-(2-pyridyl)thiopropanamide. 1

By the same procedure." using Z-(dimethylaminQmethyl)-pyrrole. the productis N-allyl-2-dimethylamino- 2-( 2-pyrrolyl )-thioacetamide.

EXAMPLE 7 Alternatively. N-allyl-2'-(2-pyridyl)thioacetamide is prepared by the following procedure.

Allylamine (3.1 g.) is added with stirring to 4.0 g. of 2-(2-pyridyl)thioacetamide in 20 ml. of water at C. The resulting mixture is allowed to stand overnightat C.. then 5 ml. of ethanol is added.'The mixture is stirred for 5 hours and then extracted with dichloromethane. The extracts are dried and concentrated and the residue is chromatoraphed on a silica gel drycolumn to give N-allyl 2-(2-pyridyl)thioacetamide.

EXAMPLE 8 By the procedure of Example 7. reacting 2-(2- pyridyl)-4-thiopentenamide with allylamine gives N- allyl-2-( Z-pyridyl )-4-thiopentenamide.

EXAMPLE 9 To cold 2-pyridinecarboxaldebyde (21.4 g.. 0.2 mole) is added dimethylamine (22.5 g. 0f a 40 percent aqueous solution. 0.2 mole) and the solution is neutralized with concentrated hydrochloric acid. To the stirred neutralized solution is added l4.4 g. (0.22 mole) of potassium cyanide. The mixture is stirred overnight. then diluted with water. trunsferredto a separatory funnel and repeatedly extracted with chloroform. The combined chloroform extracts are washed three times with water. once wit brine and dried over magnesium sulfate. The mixture-is filtered. the solvent is removed under reduced pressure and methanol is added to the residue. The mixture is allowed to stand at -2()(. for l8 hours. then filtered. The filtrate is concentrated and distilled in vacuo to give 2- dimethylamino-2-( Z-pyridyl )acetonitrile.

2-Dimethylamino-2-(2-pyridyl)acctonitrile (l 1.4 g..

0.07 m.) is dissolved in 200 ml. of dry pyridine contain-.

ing 5 ml. ofanhydrous tricthylaminc. Hydrogen sulfide is bubbled into the stirred solution for 7 hours and the solution is then stirred for 17 hours. This procedure is repeated for 5 days. Then the mixture isstirred for an additional 48 hours. The solvent is then removed under reduced pressure and the residue is recrystallized from ethanol to give 2-dimethylamino-2-(2- pyridyllthioacetamide.

2-Dimethylamino-2-(Z-pyridyl )thioacctamide is reacted with allylamine by the procedure of Example 7 tuted acetonitriles:

5 2-diethylamino-2-(2-pyridyl)acetonitrile 2-pyrrolidino-2-( 2-pyridyl )acetonitrile 2-piperidino-2-(2-pyridyl)acetonitrile 2-dimethylamino2-(2-quinolyl)acetonitrile 2-piperidino-2-( Z-quinollyl)acetonitrile lo the products are. respectively:

N-allyl-2-diethylumino-2-( 2-pyridyl)thioacetamidc N-allyl-2-pyrrolldlno-2-(2-pyrldyl)thloncctamldo N-allyI-2-plperldlno-2-(Z-pyrldyl)thloueetamlde N-allyl-Z-dlmethylamlno-2-(2- quinolyl)thioacetamide N allyl-2-piperidino-2-(2-quinolyl)thioacetamide. Also. by the same procedure. using a N-lower ulkylpipernzine in place 'of dim-ethylamine. the N-allyl-2-( 4- lower alkylpiperazino)-T2-(2pyridyl)thioacetamides. such as the 4-methylpiperazino and 4-ethylpiperazino compounds. are obtained.

Similarly. using morpholine in place ine. the product pyridyl )thioacetamide.

EXAMPLE l0 By the procedure of Example 3. using in place of morpholine. the following compounds:

diethylamine dipropylamine dibutylamihe pyrrolidine piperidine N-methylpiperazine N-ethylpiperazlne N-propylpiperazine N-butylpiperazine the products are. respectively:

N-allyl-3-diethylamino-2-(2-pyridyl)thiopropanamide N-allyl-3-dipropylamino-2-( 2-pyridyl )thiopropanamide N-allyl-3-dibutylamino--2-(2-pyridyl)thiopropana- 'mide N-allyl-3-pyrrolidino-2-( Z-pyridyl )thiopropanamide N-allyl-S-piperidino-Z-tZ-pyridyl)thiopropunamidc N-allyl-3-(4-methylpiperazino)-2-(2-pyridyl)thiopropanamide N-allyl-3-(4-ethylpiperazino )-2-( Z-pyridyl )thiopropanamide N-allyl-3-(4-propylpiperazino)-2-(2-pyridyl)thiopropanamide N-allyl-3-(4-butylpiperazino )-2-( Z-pyridyl )thio propanamide.

is N-allyl-2-morpholino-2-(2- EXAMPLE 11 By the procedure of Example 7. 2-benzyl-2-(2- pyridyl)thioacetamide is reacted with allylamine to give N-allyl-2-benzyl-2-( Z-pyridyl )thioacetamide.

EXAMPLE 1?.

of dimethylam- 7 2-(Z-pyridyl)thiopentanamide 2-(2-pyridyl)thiohexanamide 2-( 2-pyridyl )-4 -thiopentenamide 2-(4-chlorophenyl)-2-(2-pyridyl)thioacetamide 2-benzyl-2-(2-pyridyl)thioacetamide- '5 the products are. respectively:

3-methyl-N-propargyl-2-(Z-pyridyl)thiobutanamide 2-phenyl-N-propargyl-2-( Z-pyridyl )thioaeetamide N-propargyl-2-(Z-pyridyl)thiopropanamide N-propargyl-2-(2-pyridyl)thiobutanamide N-propargyl-2-(Z-pyridyl)thiopentanamide N-propargyl-2-l2-pyrldyl)thlohexanamlde N-propargyl-2-t2-pyrldyl)-4-thlopentcnamlde 2-(4-chloropheuy!)-N-propargyl-2-(2- pyridyl)thioacetamide Z-benzyl-N-propargyl-Z-t2-pyridyl)thioacetamide.

EXAMPLE l3 By the procedure of Example 7. using in place of allylamine. the following amines:

Z-ethylallylamine l-methylallylamine 2-methylallylamine Z-butenylamine 4-methyl-2-pentenylamine lethyll -methyl-2-propynylamine Z-butynylamine Z-pentynyIamine the products are. respectively:

N-(Z-ethylallyl)-2-(2-pyridyl)thioacetamide N-( l-methylallyl)-2-(2-pyridyl )thioacetamide N-(2-methylallyl)-2-(2-pyridyl)thioacetamide N-(2-butenyl)-2-(2-pyridyl)thioacetamide N-(4-methyl;-2-pentenyl)-2-(2- pyridyl)thioacetamide N-( l-ethyl-l-methyl-2-propynyl)-2-(2- pyridyl)thioacetamide N-(2-butynyl)-2-(2-pyridyl)thioacetamide N-(2-pentynyl)-2-(Z-pyridyUthioacetamide.

EXAMPLE l4 2-(Chloromethyl)pyridine hydrochloride 16.3 g.. 0.1 mole) is dissolved in 100 ml. of methanol. Sodium ethoxidc (0.22 mole of sodium dissolved in I50 ml. of ethanol) is added dropwise. The resulting mixture is heated at reflux for l8 hours. then filtered. The filtrate is concentrated. Water and ether are added. the aqueous phase is extracted with ether and the combined ethereal phases are washed with water and saturated aqueous sodium chloride. then dried over magnesium sulfate. concentrated and distilled to give Z-(ethoxymethyl)pyridine.

By the procedure of Example 4. using Z-(ethoxymethyl)pyridine in place of Z-(methoxymethyl)pyridine. 5 the product is N-allyl-2-ethoxy-2-(2- pyridyl)thioacetamide.

Similarly. using in place of sodium ethoxide. the following sodium alkoxides:

sodium propoxide sodium hutoxide sodium allyloxide sodium eyelopropanemethoxide the products are. respectively:

N-allyl-2-propoxy-2-( Z-pyridyl )thioacetamide N-allyl-2-butoxy-242-pyridyl)thioacetamide N-allyl-2-allyloxy'2-( 2-pyrldyl )thloaeetamide 8 N-allyl-Z-cyclopropanemethoxy-2-(2- pyridyl )thioacetamide.

EXAMPLE l5 2-(6-Methyl-2pyridyl)-3-butcncnitrile [prepared by treating a-(6-methyl-2-pyridyl)-2-propenol with thionyl chloride and reacting the resulting 2-( l-chloro-2- propenyl)-6-methylpyridine with sodium cyanide] is treated with hydrogen sulfide by the procedure described in Example 9. to give 2--(6-methyl-2-pyridyI)-3- thiobutenumide.

Reacting 2-(6-methyl-2-pyrldyl)-3-thlohutenamide with ullylamlne by the procedure of Example 7 gives N-a|lyl-26-methyl-2-pyridyl)-3-thlobutcnamlde.

EXAMPLE l6 A solution of 5.9 g. of 2-pyridylacetonitrile in 15 ml.

of dimethylsulfoxide is added to a suspension of L2 g..

of sodium hydride in 25 ml. oil dimethylsull'oxide with stirring. The mixture is heated on a steam bath for 2 hours. then cooled to room temperature. l-Chloro-2- butene (4.5 g.) is added dropwise with stirring. The mixture is heated on a steam bath. with stirring, for 10 hours. then most of the solvent is removed in vacuo.

Water is added to the residue. then IOU ml. of ether is added. The ethereal solutionr is separated from the aqueous layer and rinsed several times with water. then dried. concentrated and distilled to give 2-(2-pyridyl)- 4-hexenenitrile.

The aboveprepared nitrile is treated with hydrogen sulfide by the procedure of Example 9 to give 2-(2- pyridyl)-4-thiohexenamide.

Reacting 2-(2-pyridyl)-4-thi.ohexenamide with allylamine by the procedure of Example 7 gives N-allyl-2- (Z-pyridyl)-4-thiohexenamide.

EXAMPLE l7 EXAMPLE l8 Treating N-allyl-2-(2-pyridyl)thioacetamide with an cquimolar amount of maleic acid in ethanol. then removing the solvent under reduced pressure gives N- allyl-2-( Z-pyridyl )-thioacetamide maleate.

Similarly. using citric acid. N-allyl-2-(2-pyridyl)- thioacetamide 'eitrate is prepared.

9 The ingredients are mixed and filled into a hard gelatin capsule.

EXAMPLE 20 The sucrose. calcium sulfate dihydrate and N-allyl-3- morpholino-2-(Z-pyridyl)thiopropionamidc are thoroughly mixed and granulatedwith l percent gelatin solution. The wet granules are screened. dried and then mixed with the starch. talc and stearic acid. screened and compressed into a tablet.

The compositions prepared as in Examples l9 and are administered orally to a subject having excessive gastric acid secretion within the dose ranges given hereabove.

What is claimed is:

l. A pharmaceutical composition having gastric acid secretion inhibitory activity, in dosage unit form, comprising a pharmaceutical carrier and a gastric acid secretion inhibiting amount of a thioamide compound of the formula:

in which:

R. is 2-pyridyl; R is hydrogen, lower alkyl. lower alkenyl. lower alkoxy. allyloxy. cyclopropanemethoxy. phenyl or henzyl and R is an allyl or propargyl group optionally substituted by methyl or ethyl groups, said R having 3-6 carbon atoms or a pharmaceutically acceptable acid addition salt thereof.

2. The pharmaceutical composition of claim I in which R, is hydrogen or lower alkyl and R is allyl optionally substituted by methyl or ethyl. said R havin 3-6 carbon atoms.

3. The pharmaceutical composition of claim I in which R, is hydrogen or lower alkyl and R. is allyl.

4. The pharmaceutical composition of claim I in which the thioamide compound is N-allyl-2-(2- pyridyl )thioucctamidc.

5. The pharmaceutical composition of claim I in which the thioamide compound in n-allyl-Z-methoxy-Z- (I-pyrldyl )thloacetamltle.

6. The pharmaceutical composition of claim l in which the thioamide compound is present in an amount of from about l0 mg. to about 500 mg.

7. A method of inhibiting gastric acid secretion in an animal in need thereof which comprises administering internally to said animal an effective gastric acid inhibiting amount of a thioamide compound of the formula:

CH-j -NH-R. R-, J

in which:

R. is 2-pyridyl;

R is hydrogen. lower alkyl, lower alkenyl, lower alkoxy. allyloxy, cyclopropanemethoxy. phenyl or benzyland R is an allyl or propargyl group optionally substituted by methyl or ethyl groups. said R having 3-6 carbon atoms or a pharmaceutically acceptable acid addition salt thereof.

8. The method of claim 7 in which the thioamide compound is N-allyl-2-(2-pyridyl)thioacetamide.

9. The method of claim 7 in which the thioamide compound is N-allyl-2-methoxy-2-( 2- pyridyl)thioacctamide.

ID. The method of claim 7 in which the thioamide compound is administered in a daily dosage of from about 10 mg. to about 2 g.

l I t UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. 1 3, 897,555 DATED y 29, 1975 |NvENTOR(5) Bernard Loev It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 47, "-C should read -CH Column 3, line 6, "emulsion" should read emulsions Column 3, line 8, "composition" should read compositions Column 8, line 14, "N-allyl-26-methyl-" should read N-allyl-2-(6-methyl- Column 10, line 11, n-allyl-" should read N-allyl- Signcd and Scaled this twenty-eight Day Of October 1975 [SEAL] A ttes t:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner oj'lalents and Trademarks 

1. A PHARMACEUITICAL COMPOSITION HAVING GASTRIC ACID SCRETION INHIBITORY ACTIVITY, IN DOSAGE UNIT FORM, COMPRISING A PHARMACEUTICAL CARRIER AND A GASTRIC ACID SECRETION INHIBITING AMOUNT OF A THIOAMIDE COMPOUND OF THE FORMULA:
 2. The pharmaceutical composition of claim 1 in which R2 is hydrogen or lower alkyl and R3 is allyl optionally substituted by methyl or ethyl, said R3 having 3-6 carbon atoms.
 3. The pharmaceutical composition of claim 1 in which R2 is hydrogen or lower alkyl and R3 is allyl.
 4. The pharmaceutical composition of claim 1 in which the thioamide compound is N-allyl-2-(2-pyridyl)thioacetamide.
 5. The pharmaceutical composition of claim 1 in which the thioamide compound is n-allyl-2-methoxy-2-(2-pyridyl)thioacetamide.
 6. The pharmaceutical composition of claim 1 in which the thioamide compound is present in an amount of from about 10 mg. to about 500 mg.
 7. A method of inhibiting gastric acid secretion in an animal in need thereof which comprises administering internally to said animal an effective gastric acid inhibiting amount of a thioamide compound of the formula:
 8. The method of claim 7 in which the thioamide compound is N-allyl-2-(2-pyridyl)thioacetamide.
 9. The method of claim 7 in which the thioamide compound is N-allyl-2-methoxy-2-(2-pyridyl)thioacetamide.
 10. The method of claim 7 in which the thioamide compound is administered in a daily dosage of from about 10 mg. to about 2 g. 